Hydrogen is a future clean energy, and has been applied in various fields such as process industries, fuel cells, and separation and storage of hydrogen. Since there is a danger of ignition or explosion when hydrogen is present at a concentration of 4% or greater in the air, a hydrogen detection sensor may be a very important factor for safety. In particular, since hydrogen has a high diffusion rate and the detection of hydrogen is easily affected by environmental conditions, it is an appropriate safety strategy to provide as many sensors as possible by using inexpensive sensors.
Recently, studies on a hydrogen sensor using a metal oxide of WO3 have been conducted. For example, a nanocomposite particle sensor using WO3 nanoparticles has been synthesized and the nanoparticles are so small that the contact area of a catalyst reduced by hydrogen in the air with WO3 can be greatly increased. This sensor method may be used as a chemochromic sensor in which colors are changed without an external power source under the hydrogen exposure conditions. However, in the hydrogen sensor using WO3, the reaction efficiency and reliability of the sensor may deteriorate over time as the ability of the catalyst particles to decompose hydrogen molecules into atoms by reacting with oxygen or water steam in the external environment rapidly may decline over time.
Therefore, there is a need for developing a new detection sensor which is inexpensive and produced by a simple process, and secures durability without adversely affecting the sensitivity and responsiveness of the sensor.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.